Add kboot.conf parser

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>

2 files changed, 236 insertions, 1 deletions

diff --git a/devices/kboot-parser.c b/devices/kboot-parser.c
new file mode 100644
index 0000000..27f3025
--- /dev/null
+++ b/devices/kboot-parser.c
@@ -0,0 +1,233 @@
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <ctype.h>
+#include <unistd.h>
+
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include "udev-helper.h"
+#include "params.h"
+
+#define buf_size 1024
+
+static const char *mountpoint;
+
+static int param_is_ignored(const char *param)
+{
+	static const char *ignored_options[] =
+		{ "message", "timeout", "default", NULL };
+	const char **str;
+
+	for (str = ignored_options; *str; str++)
+		if (streq(*str, param))
+			return 1;
+	return 0;
+}
+
+/**
+ * Splits a name=value pair, with value terminated by @term (or nul). if there
+ * is no '=', then only the value is populated, and *name is set to NULL. The
+ * string is modified in place.
+ *
+ * Returns the next byte to process, or null if we've hit the end of the
+ * string.
+ *
+ * */
+static char *get_param_pair(char *str, char **name_out, char **value_out,
+		char terminator)
+{
+	char *sep, *tmp, *name, *value;
+
+	/* terminate the value */
+	tmp = strchr(str, terminator);
+	if (tmp)
+		*tmp = 0;
+	else
+		tmp = NULL;
+
+	sep = strchr(str, '=');
+	if (!sep) {
+		*name_out = NULL;
+		*value_out = str;
+		return tmp ? tmp + 1 : NULL;
+	}
+
+	/* terminate the name */
+	*sep = 0;
+
+	/* remove leading spaces */
+	for (name = str; isspace(*name); name++);
+	for (value = sep + 1; isspace(*value); value++);
+
+	/* .. and trailing ones.. */
+	for (sep--; isspace(*sep); sep--)
+		*sep = 0;
+	for (sep = value + strlen(value) - 1; isspace(*sep); sep--)
+		*sep = 0;
+
+	*name_out = name;
+	*value_out = value;
+
+	return tmp ? tmp + 1 : NULL;
+}
+
+static int parse_option(struct boot_option *opt, char *config)
+{
+	char *pos, *name, *value, *root, *initrd, *cmdline, *tmp;
+
+	root = initrd = cmdline = NULL;
+
+	/* remove quotes around the value */
+	while (*config == '"' || *config == '\'')
+		config++;
+
+	pos = config + strlen(config) - 1;
+	while (*pos == '"' || *pos == '\'')
+		*(pos--) = 0;
+
+	if (!strlen(pos))
+		return 0;
+
+	pos = strchr(config, ' ');
+
+	/* if there's no space, it's only a kernel image with no params */
+	if (!pos) {
+		opt->boot_image_file = join_paths(mountpoint, config);
+		opt->description = strdup(config);
+		return 1;
+	}
+
+	*pos = 0;
+	opt->boot_image_file = join_paths(mountpoint, config);
+
+	cmdline = malloc(buf_size);
+
+	for (pos++; pos;) {
+		pos = get_param_pair(pos, &name, &value, ' ');
+
+		if (!name) {
+			strcat(cmdline, " ");
+			strcat(cmdline, value);
+
+		} else if (streq(name, "initrd")) {
+			initrd = value;
+
+		} else if (streq(name, "root")) {
+			root = value;
+
+		} else {
+			*(value - 1) = '=';
+			strcat(cmdline, name);
+		}
+	}
+
+	if (initrd) {
+		asprintf(&tmp, "initrd=%s %s", initrd, cmdline);
+		free(cmdline);
+		cmdline = tmp;
+
+		opt->initrd_file = join_paths(mountpoint, initrd);
+	}
+
+	if (root) {
+		asprintf(&tmp, "root=%s %s", root, cmdline);
+		free(cmdline);
+		cmdline = tmp;
+
+	} else if (!initrd) {
+		/* if there's an initrd but no root, fake up /dev/ram0 */
+		asprintf(&tmp, "root=/dev/ram0 %s", cmdline);
+		free(cmdline);
+		cmdline = tmp;
+	}
+
+	printf("kboot cmdline: %s", cmdline);
+	opt->boot_args = cmdline;
+
+	asprintf(&opt->description, "%s %s", opt->boot_image_file, cmdline);
+
+	return 1;
+}
+
+static void parse_buf(struct device *dev, char *buf)
+{
+	char *pos, *name, *value;
+	int sent_device = 0;
+
+	for (pos = buf; pos;) {
+		struct boot_option opt;
+
+		pos = get_param_pair(pos, &name, &value, '\n');
+
+		printf("kboot param: '%s' = '%s'\n", name, value);
+
+		if (name == NULL || param_is_ignored(name))
+			continue;
+
+		memset(&opt, 0, sizeof(opt));
+		opt.name = strdup(name);
+
+		if (parse_option(&opt, value))
+			if (!sent_device++)
+				add_device(dev);
+			add_boot_option(&opt);
+
+		free(opt.name);
+	}
+}
+
+static int parse(const char *devicepath, const char *_mountpoint)
+{
+	char *filepath, *buf;
+	int fd, len, rc = 0;
+	struct stat stat;
+	struct device *dev;
+
+	mountpoint = _mountpoint;
+
+	filepath = join_paths(mountpoint, "/etc/kboot.conf");
+
+	fd = open(filepath, O_RDONLY);
+	if (fd < 0)
+		goto out_free_path;
+
+	if (fstat(fd, &stat))
+		goto out_close;
+
+	buf = malloc(stat.st_size + 1);
+	if (!buf)
+		goto out_close;;
+
+	len = read(fd, buf, stat.st_size);
+	if (len < 0)
+		goto out_free_buf;
+	buf[len] = 0;
+
+	dev = malloc(sizeof(*dev));
+	memset(dev, 0, sizeof(*dev));
+	dev->id = strdup(devicepath);
+	dev->icon_file = strdup(generic_icon_file(guess_device_type()));
+
+	parse_buf(dev, buf);
+
+	rc = 1;
+
+out_free_buf:
+	free(buf);
+out_close:
+	close(fd);
+out_free_path:
+	free(filepath);
+	return rc;
+}
+
+struct parser kboot_parser = {
+	.name = "kboot.conf parser",
+	.priority = 98,
+	.parse	  = parse
+};
diff --git a/devices/udev-helper.c b/devices/udev-helper.c
index da12129..1db8a26 100644
--- a/devices/udev-helper.c
+++ b/devices/udev-helper.c
@@ -26,6 +26,7 @@
 
 extern struct parser native_parser;
 extern struct parser yaboot_parser;
+extern struct parser kboot_parser;
 static FILE *logf;
 static int sock;
 
@@ -33,6 +34,7 @@ static int sock;
 static struct parser *parsers[] = {
 	&native_parser,
 	&yaboot_parser,
+	&kboot_parser,
 	NULL
 };
 
@@ -48,7 +50,7 @@ static void iterate_parsers(const char *devpath, const char *mountpoint)
 		log("\ttrying parser '%s'\n", parsers[i]->name);
 		/* just use a dummy device path for now */
 		if (parsers[i]->parse(devpath, mountpoint))
-			return;
+			/*return*/;
 	}
 	log("\tno boot_options found\n");
 }